Do check your ignition switch. As has already been said, you need power while cranking and my series 3 had to be rewired to provide that when I put the 3.9 in - took me a while to figure it out

Just done the HGs on my Disc 4L. It is not too hard - just long winded. The heads cost me £96 all in to have skimmed. I decent HG set with new bolts etc was £70. New oil and antifreeze (OAT) is another £40 so that's just over £200 plus a shed load of labour. I've just noticed yours is a 3.9...

Medusa - that's a surprise. RPi recommend it for Offroad. Reckon it's brill. Is that not so?

I wouldn't ditch the SUs just yet. They can run at weird angles and don't take loads of effort to tune up. I've got them on the 3.9, the Tr7V8 and the Etype Try running with out oil in the dash pots for some serious accel, solder the run-on valves shut and play with some needles. Scott Bevis...

You don't really need a torque angle thingy. Mine tightened to 22nm then I put a spot of tipex on the bolts at one point. Tighten them up until the tipex mark is the other side (180 degrees) and you are done - easy really

Get a piece of pipe up to your ear and the other end directed down where you hear the noise. Should enable you to isolate where it's coming from a little more.

Efi? Carbs? Gems? - some more info would help

On the V8 (I presume you mean this) the throttle body bolts to the plenum with four bolts

I rang Burlen - very 'helpful' bloke said he could only advise on standard set ups, not a 3.9 with carbs. He did point me to a section of the website which enables you to compare up to five needles against each other Minty SU Needle Compare-o-rama which helped a little and I downloaded a nice...

According to RAVE tighten all to 15lbs ft (20Nm) then turn a further 90 degrees then another 90 degrees. Do not do 180 degrees in one go. You will need to buy new bolts as yours will have expanded

I've just taken the Efi off the 3.9 and replaced it with twin SUs from an SD1. Goes really well apart from the top end. I assume I need to replace the needles for something richer but does anyone know which needles I need?

Ok I'm going to hold my hands up now........ I got all the injectors off and made up a brill test rig, cleaned them all, worked them through on the rail etc etc etc. Got it all back on and still got a misfire - bugger! Started at the beginning again with the ignition. Plugs - check HT...

Well remembered - it is 38nm I think the sequence for the head bolts depends on your engine. On the 3.9 (both types) you work from the centre head bolts outwards to the edge but on one type the outer row was only 60nm while the rest were 90nm. On Suffix B there was a 2 stage tightening...

Don't think it's mechanical - the rockers and pushrods move up and down the same amount as the others. I have had the cam problem on a 4.0L and it ticked badly - this one doesn't I've had the Noid light on and all the wiring seems fine. I've also had the Injectors off again. the solenoids...

Thanks Joe - I've ordered the Noid light and will see if that is the problem. Never heard of these before so thanks for the info

There is no problem with the sparkys. If you swop the plugs around or the plug leads it still won't fire on No1. I'm almost convinced it is an injector problem - just need to know how to check the wiring as the continuity test via the ECU plug seems ok

OEM Cap and rotor, Magnecor leads, NGK sparkys (can't remember the number but the recommended ones) all replaced at the same time. The spark to all the plugs is good and strong

How can I check the injector wiring on the 3.9Efi. I have a problem with one cylinder that won't fire and it is driving me mad So far I've checked and done: New plugs and leads Good spark at all the plugs Nothing is wrong when you run the tests on the ECU Plug as per the book The...

Yea it is sparking, new plugs as well. I'll do the test lamp thing but I'm thinking valve or cam - such is life

I haven't done a compression test - can't find my tester anywhere (must have lent it to someone) so I'll get another next week. How do you do a compression test without a gauge by the way? thumb over the hole? No odd noises anywhere, the multimeter test for volts and resistance (via the ECU...